Long COVID, also known as post-acute sequelae of SARS-CoV-2 infection (PASC), post-COVID syndrome, or chronic COVID syndrome, refers to a range of symptoms and health problems that persist or develop after the initial acute phase of a COVID-19 infection. These symptoms last for at least three months after the initial infection and can continue for weeks, months, or even years
Key Characteristics of Long COVID
- Symptoms: Common symptoms include extreme fatigue, shortness of breath, cognitive difficulties often called "brain fog," heart palpitations, headaches, sleep disturbances, loss of taste or smell, muscle weakness, and mental health issues. Symptoms may fluctuate, worsen after physical or mental exertion (post-exertional malaise), or reoccur over time
- Impact: Long COVID can be debilitating, affecting daily functioning and quality of life. It may require comprehensive medical care and can sometimes lead to disability
- Prevalence: Estimates suggest about 6–7% of adults and around 1% of children experience long COVID symptoms, though figures vary by study and population. Vaccination reduces the risk of developing long COVID
- Risk Factors: Higher risk is associated with female sex, older age, having asthma or cardiovascular disease, and experiencing a more severe initial COVID-19 illness
- Causes: The exact cause is not fully understood. Hypotheses include lasting organ or blood vessel damage, immune system dysfunction, persistent virus or reactivation of latent viruses, and problems with blood clotting or neurological function
- Diagnosis and Management: Diagnosis is based on history of COVID-19 infection and exclusion of other causes. There is no single treatment; management focuses on symptom relief and supportive care. Rest and pacing activity are recommended for fatigue and post-exertional malaise
Definitions
- The World Health Organization (WHO) defines long COVID as symptoms starting three months after infection and lasting at least two months without alternative diagnosis
- The U.S. Centers for Disease Control and Prevention (CDC) defines it as symptoms persisting at least four weeks after infection
- The British National Institute for Health and Care Excellence (NICE) categorizes it into ongoing symptomatic COVID-19 (4–12 weeks) and post-COVID-19 syndrome (beyond 12 weeks)
In summary, long COVID is a complex, chronic condition following COVID-19 infection with a wide variety of symptoms that can significantly impair health and daily life. It remains an active area of research for better understanding and treatment
